Hydrogenation Effect on Hole-Transport Properties of Fullerene C70: A Density Functional Theory Study on C70H4, C70H6, and C70H8

Reorganization energies λ of isomers of hydrogenated fullerenes, C70H n (n = 4, 6, 8), are investigated by the density functional theory (B3LYP/6–311G**). The smallest value of λ (λ min) of C70H4 is 74 meV and is smaller than those of C70H2 (79 meV) and C60H4 (83 meV). λ min of C70H6 and C70H8 are 72 meV and 74 meV, respectively. Addition of H atoms to [6,6]-ring fusion generally gives smaller λ than that to [5,6]-ring fusion. Hydrogenation can reduce λ min of C70 materials and the result that C70H6 has the smallest λ min is same with the result of hydrogenation of C60.